Patients With Atopic Dermatitis Sensitized to Pet Dander Mount IgE and T-Cell Responses to Mammalian Cystatins, Including the Human Self-Protein.

BACKGROUND: Immediate and delayed-type hypersensitivity reactions to pet-borne allergens are common in atopic diseases. In atopic dermatitis (AD), controversy surrounds the contribution to the disease of cross-reactivity to self-proteins. Human cystatin A and the cat allergen Fel d 3 belong to the cystatins, an evolutionary conserved protein family. The objective of the present study was to assess crossreactivity between mammalian cystatins and to analyze T-cell responses to cystatin in AD patients sensitized to pet dander. METHODS: cDNA coding for dog cystatin was cloned from dog skin. Sera from 245 patients with IgE-mediated sensitization to cat and dog dander were tested for IgE binding to recombinantly expressed feline, canine, and human cystatin. Of these, 141 were also diagnosed with AD. RESULTS: Cystatin-specific IgE was detected in 36 patients (14.7%), of whom 19 were considerably affected by AD. Within the AD patients, 9 had measurable IgE against all 3 cystatins. Cystatin-sensitized AD patients did not differ from non-cystatin-sensitized patients in terms of disease severity, age, or total IgE levels. T-cell cytokine measurements showed elevated IL-4 levels after stimulation with feline and human cystatin. CONCLUSIONS: The humoral response suggests that in addition to Fel d 3, the homologous protein from dog might play a role in allergy. Furthermore, human cystatin appears to be capable of driving a type 2 immune response in sensitized AD patients and may therefore be considered a so-called autoallergen, as proposed for other evolutionary conserved proteins.

8,9-Didehydrofluoranthenes as building blocks for the synthesis of extended polycyclic aromatic hydrocarbons (PAHs).

[reaction: see text] The synthesis of phenyl-substituted 8,9-dibromofluoranthene and p-dodecylphenyl-substituted 8,9-fluoranthene anthranilic acid is presented. Their synthetic potential as 8,9-didehydrofluoranthene precursors is demonstrated in combination with a new biscyclopentadienone by the synthesis of novel phenyl-substituted PAHs with up to 14 annulated rings. The crystal structure of 7,16-diphenylfluorantheno[8,9-k]fluoranthene is given.

Origin and environmental setting of ancient agriculture in the lowlands of Mesoamerica.

Archaeological research in the Gulf Coast of Tabasco reveals the earliest record of maize cultivation in Mexico. The first farmers settled along beach ridges and lagoons of the Grijalva River delta. Pollen from cultivated Zea appears with evidence of forest clearing about 5100 calendar years B.C. (yr B.C.) [6200 (14)C years before the present (yr B.P.)]. Large Zea sp. pollen, typical of domesticated maize (Zea mays), appears about 5000 calendar yr B.C. (6000 yr B.P.). A Manihot sp. pollen grain dated to 4600 calendar yr B.C. (5800 yr B.P.) may be from domesticated manioc. About 2500 calendar yr B.C. (4000 yr B.P.), domesticated sunflower seeds and cotton pollen appear as farming expanded.

Syntheses of halogenated ethenyl isocyanide chromium complexes as organometallic precursor molecules for ethenyl and ethynyl isocyanides.

The radical alkylation of tetraethylammonium pentacarbonyl(cyano)chromate 1 yielded the halogenated ethyl isocyanide complexes [(CO)5Cr(CN-CClX-CClYF)] 3 (a, X= Cl, Y= F; b, X = F, Y= F and c, X=Y= Cl). Dehalogenation of 3 using zinc in diethyl ether gave [(CO)5Cr(CN-CX=CFY)] 4. The compounds 4a, b reacted with various nucleophiles exclusively at the difluoromethylene group. The unstable phosphorane 5, which is formed on reaction of 4b with trimethylphosphane, decomposed thermally and on hydrolysis yielding pentacarbonyl(1,2-difluoroethenyl isocyanide)chromium (6). The cyano substituent can be introduced in the beta position of the isocyanide function by reaction of 4a, b with potassium cyanide, leading to the formation of [(CO)5Cr(CN-CX=CF-CN)] (7). Reactions of 4a, b with organolithium or organomagnesium compounds yielded [(CO)5Cr(CN-CX=CF-R)] (8) and [(CO)5Cr(CN-CF=CF-C...C-CF=CF-NC)Cr(CO)5] (10). The trimethylsilyl group in 8a, b, d could be removed by a solution of potassium carbonate in methanol leading to [(CO)5Cr(CN-CX=CF-Cn-H)] (11) (n=2,4). Octacarbonyldicobalt reacted with 8e under coordination of the C-C triple bond to the hexacarbonyldicobalt fragment, resulting in the cluster compound 12. The crystal and molecular structure of 8i, 11 a, b, and 12 were elucidated by X-ray crystallography. The alkenyl and alkynyl isocyanides CN-CCl=CF2 (13a), CN-CF=CF2 (13b), CN-CCl=CClF (13c), CN-CF=CFH (14), CN-CC-H (15), CN-CC-CN (16), and CN-CCl=CF-CN (17) were obtained by flash vacuum pyrolysis of 4a, 4b, 4c, 6, and 7a, respectively.

Mesoderm-independent regulation of gastrulation movements by the src tyrosine kinase in Xenopus embryo.

In vitro studies have demonstrated the involvement of Src kinases in several aspects of cell scattering, including cell dissociation and motility. We have therefore sought to explore their functions in the context of the whole organism. Loss-of-function microinjection studies indicate that the ubiquitous Src, Fyn, and Yes tyrosine kinases are specifically implicated in Xenopus gastrulation movements. Injection of mRNAs coding for dominant negative forms of the ubiquitous members of the Src family, namely Fyn, Src, and Yes, perturbs gastrulation movements, resulting in the inability to close the blastopore. Injection of mRNA coding for Csk, a natural inhibitor of Src kinase activity, produces the same phenotypic alterations. The ubiquitous Src kinases have redundant functions in gastrulation movements since overexpression of one member of the family can compensate for the inhibition of another. Interfering mutants of the Src family also inhibit activin-induced morphogenetic movements of animal cap explants isolated from injected embryos. In contrast, these mutants do not interfere with mesoderm induction, as inferred from the presence of mesoderm derivatives and from the expression of early mesodermal markers in injected embryos. In addition, Src kinase activity measured by an in vitro kinase assay is elevated in gastrulating embryos and in FGF- and activin-treated animal caps, confirming the implication of Src enzymatic activity during gastrulation. Altogether, our results demonstrate that Src kinases are essential components of the machinery that drives gastrulation movements independent of mesoderm induction and suggest that Src activity is primarily implicated in cellular movements that take place during the process of cell intercalation.

Syntheses and 1H-, 13C- and 15N-NMR spectra of ethynyl isocyanide, H-C triple bond C-N triple bond C, D-C triple bond C-N triple bond C and prop-1-ynyl isocyanide, H3C-C triple bond C-N triple bond C, D3C-C triple bond C-N triple bond C: high resolution infrared specturm of prop-1-ynyl isocyanide

Ethynyl isocyanide, H-C triple bond C-N triple bond C (1a), deuteroethynyl isocyanide, D-C triple bond C-N triple bond C (1b), prop-1-ynyl isocyanide, H3C-C triple bond C-N triple bond C (1c), and trideuteroprop-1-ynyl isocyanide, D3C-C triple bond C-N triple bond C (1d) are synthesized by flash vacuum pyrolysis of suitable organometallic precursor molecules (CO)5Cr(CN-CCl triple bond CClH) (5a), (CO)5Cr(CN-CCI=CClD) (5b), (CO)5Cr(CN-CCl=CCl-CH3) (5c) and (CO)5Cr(CN-CCI=CCl-CD3) (5d), respectively. Compounds 5a-d are formed in two steps by radical alkylation of tetraethyl-ammonium pentacarbonyl(cyano)chromate, NEt4[Cr(CO)5(CN)] (2) by 1,1,2,2,-tetrachloroethane (3a), 1,1,2,2-tetrachloro-1,2-dideuteroethane (3b), 1,1,2,2,-tetrachloropropane (3c), and 1,1,2,2-tetrachloro- 1,3,3,3-tetradeutero-propane (3d) yielding [(CO)5Cr(CN-CCl2-CCl2-H)] (4a), [(CO)5Cr(CN-CCl2-CCl2D)] (4b), [(CO)5Cr(CN-CCl2-CCl2-CH3)] (4c), and [(CO)5Cr(CN-CCl2-CCl2-CD3)] (4d). Dehalogenation of 4a-d using zinc in diethylether/acetic acid gives 5a-d, respectively. A multinuclear NMR study revealed the 1H-, 13C- and 15N-NMR data of 1a and 1c. Molecular spectroscopic data of 1c were determined by high resolution infrared spectroscopy. The by-products of the pyrolysis are the E and Z isomers of the halogenated ethenyl isocyanides H(Cl)C=CCl-NC (6a) and H3C(Cl)C=CCl-NC (6c) which have been characterized by IR, MS and NMR spectroscopy.

Synthesis and an X-ray structure of soluble phenylacetylene macrocycles with two opposing bipyridine donor sites

The synthesis of the shape-persistent macrocycles 10a and 10b with two bipyridine units in opposing sides by Hagihara/Sonogashira cross-coupling chemistry of suitably functionalized building blocks is reported. X-ray analysis of single crystals of 10b shows a layered structure with channels filled with solvent molecules and parts of the flexible chains. with which the cycle is decorated for solubility reasons.

Phosphorylation of tyrosine residues 31 and 118 on paxillin regulates cell migration through an association with CRK in NBT-II cells.

Identification of signaling molecules that regulate cell migration is important for understanding fundamental processes in development and the origin of various pathological conditions. The migration of Nara Bladder Tumor II (NBT-II) cells was used to determine which signaling molecules are specifically involved in the collagen-mediated locomotion. We show here that paxillin is tyrosine phosphorylated after induction of motility on collagen. Overexpression of paxillin mutants in which tyrosine 31 and/or tyrosine 118 were replaced by phenylalanine effectively impaired cell motility. Moreover, stimulation of motility by collagen preferentially enhanced the association of paxillin with the SH2 domain of the adaptor protein CrkII. Mutations in both tyrosine 31 and 118 diminished the phosphotyrosine content of paxillin and prevented the formation of the paxillin-Crk complex, suggesting that this association is necessary for collagen-mediated NBT-II cell migration. Other responses to collagen, such as cell adhesion and spreading, were not affected by these mutations. Overexpression of wild-type paxillin or Crk could bypass the migration-deficient phenotype. Both the SH2 and the SH3 domains of CrkII are shown to play a critical role in this collagen-mediated migration. These results demonstrate the important role of the paxillin-Crk complex in the collagen-induced cell motility.

Crystal and molecular structures of trifluoroacrylonitrile, F2C=CF-CN, and trifluorovinyl isocyanide, F2C=CF-NC, by low-temperature X-ray crystallography and ab initio calculations.

The structures of trifluoroacrylonitrile, F2C=CF-CN, monoclinic, P2(1/n) (no. 14), a = 8.595(4), b = 8.748(1), c = 5.421(1) A, beta = 102.83(2) degrees, Z = 4, and its thermally unstable isomer trifluorovinyl isocyanide, F2C=CF-NC, monoclinic, P2(1/n), a = 8.501(2), b = 8.828(2), c = 5.599(2) A, beta = 101.11(2) degrees, Z = 4 were determined by X-ray crystal structure analysis at 113 and 128 K, respectively, from single crystals grown by partial melting and gradient cooling in small glass capillaries. Selected experimental bond lengths of F2C=CF-CN/F2C=CF-NC are as follows: C=C 1.326(1)/1.304(2), C...N 1.158(1)/1.167(2) A. The C-F bond lengths of the CF2 group are significantly shorter than those of the CF(NC) and CF(CN) units, respectively. The vibrational frequencies and molecular geometries of this cyanide/isocyanide pair were also calculated by ab initio methods for comparison with the experimental results, which were found to be in general agreement.

Low-temperature crystallization and structure determination of N-(trifluoromethyl)formamide, N-(2,2,2-trifluoroethyl)formamide and 2,2,2-trifluoroethyl isocyanide.

Crystals of N-(trifluoromethyl)formamide, C(2)H(2)F(3)NO, (I), N-(2,2,2-trifluoroethyl)formamide, C(3)H(4)F(3)NO, (II), and 2,2,2-trifluoroethyl isocyanide, C(3)H(2)F(3)N, (III), were grown in situ on an X-ray diffractometer and analysed by single-crystal X-ray diffraction methods at low temperatures. Crystal data: (I) orthorhombic, P2(1)2(1)2(1), a = 4.547 (2) Å, b = 5.947 (3) Å, c = 14.731 (9) Å, V = 398.3 (4) Å(3), Z = 4, M(r) = 113.05, T = 143 K, D(x) = 1.885 Mg m(-3); (II) monoclinic, P2(1)/n, a = 4.807 (1) Å, b = 16.707 (3) Å, c = 6.708 (1) Å, beta = 109.90 (1) degrees, V = 506.6 (2) Å(3), Z = 4, M(r) = 127.07, T = 141 K, D(x) = 1.666 Mg m(-3); (III) orthorhombic, P2(1)2(1)2(1), a = 5.668 (2) Å, b = 9.266 (3) Å, c = 8.626 (2) Å, V = 453.0 (2) Å(3), Z = 4, M(r) = 109.06, T = 163 K, D(x) = 1.599 Mg m(-3). The results showed that in the crystal both formamides (I) and (II) are exclusively present in the form of the Z isomer, although measurements of solutions of (I) have shown that the E isomer prevails [Lentz et al. (1987). Angew. Chem. 99, 951-953]. In addition ab initio calculations for (I) predicted the E isomer to be the more stable one. In compound (III) the isocyanide group is staggered with respect to the trifluoroethyl group. In the crystal packing of (I) and (II) intermolecular N-H.O hydrogen bonds generate infinite chains. In (I), these chains are linked to form sheets by C-H.O contacts. In the crystal structure of (III) each isocyanide dipole is surrounded by four electronegative F atoms with intermolecular C.F contacts between 3.4 and 3.5 Å.

New antifungal agents that inhibit the growth of Candida species: dichlorinated 8-quinolinols.

Five dichlorinated 8-quinolinols (2,5- 5,6-, 3,5-, 3,7-, and 4,5-dichloro-8-quinolinol) were tested against Candida albicans and C. tropicalis in Sabouraud dextrose broth with and without bovine serum. The 5,6-, 3,5-, and 3,7-dichloro-8-quinolinols proved to be more effective than the control, 5-fluorocytosine. In cytotoxicity tests employing baby hamster kidney (BHK) cells, all test agents proved to be more cytotoxic than the control. However, the minimum inhibitory concentration (MIC) of 3,5-dichloro-8-quinolinol to both fungi was only one tenth the cytotoxic dose, suggesting that the compound may be useful as a topical or systemic antifungal agent.

The Millimeter-Wave Spectrum of DCCNC

The millimeter-wave spectrum of deuteroethynylisocyanide has been observed and analyzed in the ground and in the first excited vibrational states (v4, v5, v6, v7) = (0100), (0010), and (0001). Rotational, centrifugal distortion, and l-type doubling constants are given. Copyright 1998 Academic Press.

Antimicrobial properties of Honduran medicinal plants.

Ninety-two plants used in the traditional pharmacopoeia of the Pech and neighboring Mestizo peoples of central Honduras are reported. The results of in vitro antimicrobial screens showed that 19 of the extracts from medicinal plants revealed signs of antifungal activity while 22 demonstrated a measurable inhibitory effect on one or more bacterial cultures. Bioassay-guided fractionation of extracts from Mikania micrantha, Neurolaena lobata and Piper aduncum produced weak to moderately active isolates. The broad spectrum of activity of the extracts helps to explain the widespread use of these plants for wound healing and other applications.

Acute and chronic stroke: navigated spin-echo diffusion-weighted MR imaging.

PURPOSE: The authors evaluated a phase-navigated spin-echo (SE) motion-correction sequence for use at diffusion-weighted (DW) magnetic resonance (MR) imaging after cerebral infarction. MATERIALS AND METHODS: Twenty-nine patients underwent 32 conventional T2-weighted fast SE and SE DW imaging after stroke (n=25), transient ischemic attack (n=3), or reversible ischemic neurologic deficit (n=1). Imaging was performed in a standard head holder with standard padding. Apparent diffusion coefficient (ADC) maps were constructed. RESULTS: DW images depicted high signal intensity compatible with localization of the ischemic symptoms in all cases. Lesions were depicted more clearly on DW than on T2-weighted images. On DW images, acute infarct ADC values were uniformly low (mean, 0.401x10(-5) cm2/sec =+/- 0.143 [standard deviation]) compared with control ADC values (mean, 0.754x10(-5) cm2/sec +/- 0.201). ADC values of chronic infarcts were supranormal (mean, 1.591x10(-5) cm2/sec +/- 0.840) compared with control values (mean, 0.788x10(-5) cm2/sec +/- 0.166). DW imaging did not show a change after transient ischemic attack. with reversible ischemic neurologic deficit, however, hyperintensity on DW images and low ADC resolved after symptoms abated. CONCLUSION: Clinical phase-navigated SE DW imaging improved early diagnosis of stroke and helped differentiate acute from chronic stroke. Changes on DW images are reversed after symptoms resolve.

Recovery from disuse osteopenia coincident to restoration of muscle strength in mdx mice.

The objective of this study was to compare the tibial structure and the strength of the tibia during muscle weakness and after recovery in mdx mice (which demonstrate X-linked muscular dystrophy and subsequent muscle regeneration) and age-matched control mice. The extent of disuse atrophy produced by muscle weakness and recovery following restoration of normal muscle strength could then be determined. The tibiae adjacent to weakened tibialis anterior muscles of 4-week-old mdx mice had significantly reduced radiographic density (p < 0.05) and cortical thickness (p < 0.001), and increased porosity (p < 0.001) compared to age-matched controls, suggesting development of disuse osteopenia. Significantly less force was required to break mdx tibiae than age-matched control tibiae (p < 0.05). In addition, Sharpey's fiber density was reduced (p < 0.001), suggesting a weakened attachment of the tibialis anterior muscle to bone. At 12 weeks, during the period of muscle regeneration, mdx tibial cortical thickness (p < 0.001) and porosity (p < 0.01) remained significantly lower, but percent calcium and Sharpey's fiber and radiographic densities were significantly greater (p < 0.001) than in age-matched controls, suggesting that bone mineralization and muscle attachment strength had increased to above normal levels in parallel with recovery of strength by the attached muscle. By 18 weeks, mdx tibial cross-sectional area, cortical thickness, and porosity remained significantly less (p < 0.001) than normal. Although Sharpey's fiber density was greater than in age-matched controls (p < 0.001) by 18 weeks, mdx tibial percent calcium (p < 0.005) and Sharpey's fiber density (p < 0.001) were significantly reduced from levels in 12-week-old mdx animals. There was significantly less deformation of the tibia prior to fracture in mdx than control tibiae at 18 weeks of age, suggesting tibial brittleness. Thus, at the site of attachment of mdx muscle to osteopenic bone, the remodelling which accompanies recovery of muscle strength is atypical, and produces an attachment of greater strength than function appears to require. These observations suggest that data are needed regarding bone mass and muscle-bone attachments in humans with disuse osteopenia, DMD, and other neuromuscular diseases.

MRI in varicella-zoster virus leukoencephalitis in the immunocompromised host.

Immunocompromised patients are at increased risk for CNS and disseminated varicella zoster virus (VZV) infection. In this report we present the MR findings in a leukemic patient with active, biopsy-proven VZV leukoencephalitis. The characteristic MR features of this infection were clustered subcortical plaque-like lesions demonstrating rapid demyelination. Active lesions enhanced with intravenous contrast medium administration. Edema and hemorrhage were not prominent early findings but developed as the infection evolved. These findings were strikingly similar to those reported in prior autopsy studies of immunocompromised patients with VZV leukoencephalitis.

An electron microscopic comparison of bristle end-rounding of three commercial toothbrushes.

The results from three separate examinations using SEM photomicrographs and shape factor (SF) measurements show that Oral-B P-35 brushes have a highly significant difference in bristle end-rounding when compared to Colgate Precision and Crest Complete toothbrushes. The proportion of Oral-B P-35 bristles with highly rounded ends was substantially greater than that for Colgate Precision and Crest Complete toothbrushes. Oral-B also had fewer bristles in the very sharp-edged category than both Complete and Precision toothbrushes. Each toothbrush sample in these studies was purchased from geographically dispersed retail outlets throughout the United States. Scanning electron micrographs were made from a representative random sample of bristles, then digitized and evaluated using image analysis software. The comparisons were made on the basis of the number and distribution of bristles having varying degrees of roundness as determined by shape-factor analysis. Previous studies asserted that low shape-factor values indicate sharp bristle edges that are less conducive to good oral hygiene than end-rounded bristles with high SF values. In separate studies, Oral-B P-35 had a significantly higher number of highly end-rounded bristles than did either the Colgate Precision or Crest Complete toothbrushes. The averages for end-roundness fall in the order of Oral-B P-35 > Complete > Precision. Thus we conclude that the potential for harming dental tissues is less for the Oral-B P-35 toothbrush than for either the Colgate Precision or Crest Complete toothbrushes.

Comparison of marginal adaptation between direct and indirect composites.

The evaluation of composite resin as a posterior restorative material has been slow and attended by several problems. Gap formation has been considered a serious problem by many researchers. The purpose of this in vitro study is to compare the marginal adaptation of posterior composite resins placed by a direct method with those placed by an indirect method utilizing flexible dyes. Conclusions drawn from the results of this study are that both techniques produced marginal gaps. Also there were no differences in the width of marginal gaps in the composite resin restorations placed by our direct or indirect methods, and no marginal gap differences were observed as a result of anatomical location.